Barbara McClintock's Jumping Genes
We learned in previous articles that genetic traits can be passed down from parent to child in recessive and dominant forms. Though geneticists and biologists knew this to be a fact, they could not predict which genes would manifest themselves in the succeeding offspring. Scientists knew that if they could figure out how genes were inherited instead of just confirming that they are inherited then they could answer a lot of questions regarding how certain traits become passed down through generations.
Barbara McClintock is a woman geneticist who studied the genetics and heredity of maize or corn. By looking at the reproductive cells of the plant and following these cells through mitosis, she was able to see that the chromosomes (cell parts that carry genetic traits and DNA) that divide and combine have patterns. Every child gets a set of chromosomes from one parent and another set from the other parent. These two sets combine to form a unique child.
Noticing that chromosomes have patterns are very important because as they continued to study them, they began to notice how some patterns are more likely to happen than others. This means they could measure out the probabilities that a parent would pass down a certain trait versus other traits. What's more is that she noticed that some traits can disappear and reappear over time. These were called transposable or mobile genetic elements, more popularly known as jumping genes. These jumping genes explain how we can inherit certain traits, for example eye color from our grandparents or great‐grandparents.
McClintock's discovery greatly influenced the world of science and genetics as we know it. She emphasized that the study of these transposing genes can help us learn about how living things work and how we can help living organisms respond to emotional stress since it is believed that some of these genes drive the process of evolution. Learning about jumping genes helped pave the way for current scientists to work on the human genome project. McClintock's work is an example of how dedication can really pay off. It took her years and several generations of corn to discover what she discovered. In return, she received a Nobel prize for her work and contribution to science.
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